Download BuG BReAKfASt* IN tHe BULLETIN CHlAMYDIA, GoNoRRHoeA

Bug Breakfast* in the Bulletin
Chlamydia, Gonorrhoea and Syphilis
Michelle Cretikos
NSW Public Health Officer Training Program
NSW Department of Health
Stephen Davies
Sexual Health Services
Northern Sydney Central Coast Area Health Service,
Southern Sector
Alan Brotherton
AIDS/Infectious Diseases Branch
NSW Department of Health
Chlamydia, gonorrhoea and syphilis are the three most
commonly reported sexually transmissible bacterial
infections in NSW.1 These sexually transmissible infections
(STIs) are important, not only because of their burden of
disease and long-term complications, but also because they
increase the risk of HIV transmission.2 This Bug Breakfast
provided an overview of these infections and outlined
the NSW Sexually Transmissible Infections Strategy for
2006–2009.
Chlamydia
Chlamydia is a common bacterial sexually transmissible
infection worldwide, causing more than 43 million new
chlamydial infections each year. 3 Genital chlamydia
is caused by Chlamydia trachomatis serovars D-K.
Chlamydiae are obligate intracellular parasites, and one
of the smallest of all bacteria. Transmission occurs most
commonly during sexual contact, with vertical transmission
occurring during childbirth. The incubation period is
usually seven to 14 days, and infection is commonly
asymptomatic. Recurrent infections are common.4
Genital chlamydia is one of the most frequently reported
notifiable conditions in Australia, with 35,189 diagnoses
in 2004.5 The population rate of diagnosis has more than
doubled, from 91.4 cases per 100,000 in 2000 to 186.1
cases per 100,000 in 2004.5 This rise is mostly in young
heterosexuals, and is thought to be due to a combination
of: an increase in the rate of testing of both symptomatic
and asymptomatic people; an increase in the sensitivity of
testing since the introduction of nucleic acid amplification
tests; and a real rise in the rate of infection.6, 7, 8 The longterm complications of infection are particularly severe in
women, and include pelvic inflammatory disease, infertility,
ectopic pregnancy, and chronic pelvic pain.
*Bug Breakfast is the name given to a monthly series of
hour-long breakfast seminars on communicable diseases
delivered by the NSW Department of Health’s Division of
Population Health.
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Gonorrhoea
Gonorrhoea is caused by the gram-negative bacterium
Neisseria gonorrhoeae. The incubation period of
gonorrhoea is usually two to seven days. The incidence
of gonorrhoea in Australia increased from 31.4 cases per
100,000 in 2000 to 37.0 cases per 100,000 in 2004.5 The
rates of gonorrhoeal infection are higher among Aboriginal
people compared with non-Aboriginal people, and are also
higher in the Northern Territory.5
The symptoms of gonorrhoea overlap with those of
genital chlamydia.4 Apart from urethritis, infection is
usually asymptomatic, and re-infection with gonorrhoea
is common. Complications include pelvic inflammatory
disease and infertility and, rarely, disseminated gonococcal
infection.
Syphilis
Syphilis is caused by the spirochaete bacterium, Treponema
pallidum subs. Pallidum. Transmission of syphilis occurs
through direct contact with exudative lesions, and through
vertical transmission from mother to child in utero. The
incubation period is usually between 10 and 90 days,
with an average of three weeks. Syphilis infection usually
produces a primary lesion (a chancre); however, infection
may be asymptomatic.9 Primary infection is followed by
secondary and then latent or tertiary syphilis. Syphilis
infection can have severe long-term complications if left
untreated.
In NSW, the rate of diagnosis of syphilis has almost doubled
between 2000 and 2004, with the increased rate almost
completely confined to homosexual men, particularly
those from South-East Sydney and Central Sydney who
were HIV positive, highly sexually active, or recreational
drug users.5, 9
Management of infection with chlamydia, gonorrhoea
or syphilis includes patient education, the provision of
appropriate antibiotic therapy, and contact tracing.
NSW Sexually Transmitted Infections
strategy 2006–2009:
NSW Health has recently released its first Sexually
Transmissible Infections Strategy.10 This strategy emphasises
STIs that have: significant morbidity; are associated with
poorer long-term health outcomes such as infertility;
facilitate the transmission of other infections such as
HIV; are disproportionately prevalent within vulnerable
populations; and are likely to be amenable to prevention
and control efforts. Therefore the strategy gives particular
priority to chlamydia, gonorrhoea and syphilis.
NSW Public Health Bulletin
Vol. 17 No. 5–6
The strategy identifies priority population groups
including:
•
•
•
•
•
•
•
Aboriginal people
gay and other homosexually active men
heterosexuals with recent partner change
people who inject drugs
people with HIV/AIDS
sex workers
young people.
3. World Health Organization. Revised global burden of disease
2002 estimates. WHO, Geneva. 2002. Available at www.who.
int/healthinfo/bodgbd2002revised/en/index.html
The Strategy aims to increase condom use and reduce STI
transmission rates among all priority populations. Two
specific targets have also been set in relation to syphilis
for 2009, on the advice of organisations working with key
communities. These are to:
•
•
2. Chesson HW, Pinkerton SD. Sexually transmitted diseases
and the increased risk for HIV transmission: Implications for
cost-effectiveness analyses of sexually transmitted disease
prevention interventions. J Acquir Immune Defic Syndr 2000;
24(1): 48–56.
eliminate syphilis transmission within Aboriginal
communities and
reduce rates of syphilis among gay and other
homosexually active men by 50 per cent.
Conclusion
NSW is experiencing rising rates of STIs, with increased
incidence of chlamydia primarily in young heterosexuals,
and gonorrhoea and infectious syphilis primarily in
homosexual men. The NSW Sexually Transmissible
Infections Strategy 2006–2009 aims to reduce transmission
and associated morbidities of these sexually transmissible
infections.
4. American Public Health Association. Heymann DL (Ed).
Control of communicable diseases manual (18th Edition).
Washington DC: American Public Health Association,
2005.
5. National Centre in HIV Epidemiology and Clinical Research.
HIV/AIDS, viral hepatitis and sexually transmissible
infections in Australia annual surveillance report 2005.
Canberra, National Centre in HIV Epidemiology and Clinical
Research, The University of New South Wales, and the
Australian Institute of Health and Welfare. 2005. Available
at www.med.unsw.edu.au/nchecr.
6. Burckhardt F, Warner P, Young H. What is the impact of
change in diagnostic test methods on surveillance data trends
in Chlamydia trachomatis infection? Sex Transm Infect 2006;
82: 24–30.
7. Gotz H, Lindback J, Ripa T et al. Is the increase in notifications
of Chlamydia trachomatis infections in Sweden the result of
changes in prevalence, sampling frequency or diagnostic
methods? Scand J Infect Dis 2002; 34(1): 28–34.
8. Chen MY, Donovan B. Changes in testing methods for genital
Chlamydia trachomatis in New South Wales, Australia, 1999
to 2002. Sexual Health 2005; 2(4): 251–253.
References
9. Fenyi J, Prestage G, Kippax S et al. Epidemic syphilis among
homosexually active men in Sydney. Med J Aust (2005)
183:179–183.
1. NSW Department of Health. Year in review: Communicable
disease surveillance, 2004. N S W Public Health Bull 2005;
16(5–6): 77–87.
10. NSW Department of Health. NSW Sexually Transmissible
Infections Strategy 2006–2009. Sydney: NSW Department
of Health, 2006. Vol. 17 No. 5–6
NSW Public Health Bulletin
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